Pivotal yarn support base



FIG. 1 is a perspective view of a pivotal yarn support base showing my new design;

FIG. 2 is an exploded view thereof from above; and,

FIG. 3 is an exploded view thereof from below.

The dashed lines are included for the purpose of illustration and form no part of the claimed design. 

CLAIM The ornamental design for a pivotal yarn support base, as shown and described. 